But ABI Research is predicting 64-bit chips will be on more Android mobile devices by 2018

Apple dominates 64-bit mobile chip devices as rival smartphone makers wait for a 64-bit version of the Android OS, but that early lead could dissipate in the next four years, ABI Research said on Tuesday.

The first 64-bit version of the Android OS is expected in the second half of the year. This will boost the adoption of 64-bit-compliant handsets and tablets, ABI said.

About 182 million 64-bit mobile processors will ship by the end of this year, though only 20 percent will go into Android devices, with Apple's A7 chip in the iPhone 5s and iPad tablets retaining a dominant market share, ABI said.

But as more Android 64-bit mobile devices are released in the coming years, Apple's market share in 64-bit mobile chips will decline. By 2018, 64-bit mobile processor shipments -- covering smartphones and tablets -- will total 1.12 billion, with 60 percent of those chips going into Android devices, 30 percent in Apple devices, and 9 percent in devices with Microsoft's Windows OS.

Just like on PCs, smartphones and tablets are expected to eventually transition from 32-bit to 64-bit processors. Smartphones with 64-bit processors could have more than 4GB of memory, but most devices don't need such high memory requirements yet. There will also be improvements in video performance, compression and tasks that require high degrees of processing.

Apple's iOS is 64-bit compliant, and 64-bit Android is available only for x86 processors, but not ARM, which dominates the mobile market. Google has declined to comment on the release date for a 64-bit version of Android for ARM. Development is underway for a 64-bit version of the Chrome browser for Android, and the open-source community is also developing 64-bit Android tools.

Apple surprised mobile companies with the first 64-bit iPhone 5s, which has a dual-core A7 chip. The rest of the mobile device makers are scrambling to catch up, but no other 64-bit smartphones have been announced yet. Chip makers including Intel, Qualcomm, MediaTek and Nvidia have announced 64-bit chips that could reach mobile devices starting late this year.

Industry analysts have said mobile device makers are trying to quickly move to 64-bit chips to offer user benefits, but more to keep up with Apple from a marketing perspective, and ABI Research agreed with that assessment.

While ABI is projecting 64-bit Android mobile devices for later this year, industry observers said it will initially be a trickle. A large number of 64-bit devices will likely start shipping next year, however.

Many ARM-based 64-bit chips have just been announced, and it could take nine months to a year to go through testing and validation. Nvidia and Qualcomm have said devices based on their chips will appear in the second half of the year. The initial 64-bit Android handsets could ship out with an Atom chip code-named Merrifield from Intel.